1. Technical Field
Generally the technical field relates to electronic countermeasures and more particularly to infrared countermeasure (IRCM) systems. More particularly, the technical field relates to dome coatings used in IRCM systems.
2. Background Information
An infrared countermeasure (IRCM) system is designed to protect aircraft from infrared homing (“heat seeking”) missiles by confusing the missiles' infrared guidance system so that they will miss their target. Airborne infrared countermeasure (IRCM) systems are required to defeat missile threats over a full spherical coverage of 360 degrees. To defeat advanced missile threats, high powered radar systems mounted on gimbals are firstly directed to detect the missile threats. Generally, detecting and responding to missile threats are the crucial steps to defeat the missile threats. Furthermore, since the missile threats can come from any direction, gimbals are required to quickly and accurately to respond and change their direction to where the threats are located. For these gimbals to work properly and accurately, they are needed to be protected in a sealed housing or housings, which enable a mounted infrared sensor or camera to look through domes that operate with maximum optical transmission and quality in the infrared spectrum. Thus, the window of the dome should always be clear to see through even in harsh environments. Specifically, the surface of the dome should remain clear of moisture and ice, and also should be resistant to damage from foreign objects such as sand and any type of airborne particles. Typically, materials used for infrared operation have poor thermal conductivity so that ice prevention by a traditional heating method is not the best solution to achieve a clear dome surface. Applications of direct heating with a resistive grid, convective heating with warm air inside the dome, and direct conductive heating by heating the base of the dome may work for typical visible commercial type applications. However, these types of direct heating methods sometimes interfere with precision infrared countermeasure performance. In addition, the existing heating methods are very costly, add weight to the aircraft, and consume significant energy from aircraft due to heating. However, there are no other applications that utilize extended domes with coatings that are designed to provide IR performance, durability, and anti-icing capability. Thus, there is a need for a durable, passive, and cost effective anti-icing dome coating method for infrared countermeasure (IRCM) systems.